I'm going with the phonograph platter suggestion - from the wind up, outside horn era. A lot of different companies made them (not just Victor) and some of those early platters were cast iron - maybe later ones, too. Later on they went to pressed metal in the wind up Victrola (internal horn) era. The spindle coming up from the motor fit in the hole in the middle.

I'll stick with the early 1900s wind-up phono platter. None of the field wire spool ends were cast iron (which this appears to be), all seemed to have a larger center hole than the found one, and all had at least one extra hole toward the outer edge that the wire ran through.

Originally Posted by TexaspastView post
I'll stick with the early 1900s wind-up phono platter. None of the field wire spool ends were cast iron (which this appears to be), all seemed to have a larger center hole than the found one, and all had at least one extra hole toward the outer edge that the wire ran through.

This thing is very obviously stamped sheet steel, not cast iron. I have no input on the size or placement of the holes.